Fuel injection pump for internal-combustion engines



Sept. 12, 1944.

L. BEEH 2,357,870

FUEL I NJECTION PUMP FOR INTERNALfCOMBUSTION ENGINES Filed Nov. 29 1941 4 Sheets-Sheet l INVENT OR.

LOU/'5 .355 v BY M I ATTORNEY 'Sept. 12, 1944.

1.. BEEH 2,357,870

FUEL INJECTION PUMP For: INTERNAL-COMBUSTION ENGINES Filed Nov. 29, 1941 4 Sheets-Sheet 2 INVFNTOR.

ATTORNE FUEL INJECTION PUMP FOR INTERNAL-COMBUSTION mamas Filed Nov. 29, 1941 4 Sheets-Sheet s 7a a; w

INVENTOR. 400/6 1355/9 024% C ATTOR'NE Patented Sept. 12, 1944 FUEL INJECTION PUMP FOR. INTERNAL- OOMBUSTION ENGINES Louis Beeh, Springfield, Mass.

Application November 29, 1941, Serial No. 420,992 17 Claims. (Cl. 103-41).

This invention relates to a fuel pump and more particularly to a fuel pump of the type suitable for solid injection Diesel and other internal combustion engines.

Fuel injection pumps of the type to which the invention relates are frequently used to supply measured charges of fuel underhigh pressurev and it is common practice to supply such injec-' tion pumps with fuel under a small initial pressure by means of a separate supply pump. It

is among the objects of the present invention to,

provide a supply pump which is rigidly connected with the injection pump in such a'manner that it is simultaneously actuated and controlled by the same mechanism that actuates the injection plungers.

In pumps of the type to which the invention relates it has heretofore been the practice to regulate the quantity of the fuel supplied upon each delivery stroke of the injection plunger by means of a hydraulic system connected to the fuel supply pump and dependent for its control movements upon the pressure'in the system between the supply pump and. the fuel injection plungers. Such hydraulic control systems as heretofore constructed involve a considerable amount of additional tubing between the supply pump and the injection pump, which tubing not only occupies a considerable amount of additional space but is a cause of failure in the event that any of the tubing should leak or be broken. It is among the objects of the present invention to provide such a control system in'which the passages for the Y control" fluid and the mechanism actuated thereby 'are disposed in the main pump housing or in housings rigidly and directly-connected thereto. It is a further object of the present invention to provide a fuel injection pump in which both through this spill orifice is initially at high pressure and is ejectedat high velocity. The side walls of the orifice and the cooperating surfaces of the plunger are therefore subject to a considerable amount of wear, which in time tends to reduce the accuracy with which the individual charges supplied by the plunger are measured.

It is among the objects of the present invention to greatly reduce or minimize the wear of the parts mentioned byv such an arrangement of the cooperating parts of the injection plunger and cylinder wall that new surfaces are continuously presented to the high pressure fluid to avoid undue wear at any single point.

Further objects and features of the vention will be-apparent to thoseskilled in the art from a consideration of the following detailed description taken in conjunction with the accompanying drawings in which:

Fig. 1 represents a vertical section, with parts shown in side elevation, through one of the cylinders of a multiple cylinder injection pump construoted in accordance with the present invention. I Fig. zrepresents a horizontal section taken upon the line 2-2 of Fig. 1, parts being broken away and other parts removed for the sake of clearness. 3 v Fig. 3 represents a side elevation of. the pump with parts broken away and other parts removed for the purpose showing internal structure.

Figs. 4 and 5 represent a detail of a control valve in the hydraulic control system, showing the position of the same when displaced longltudin'al- I Referring to the drawings reference numeral l0 indicates a pump housing which is provided and the cam that actuates the same by providing 1 a ball camfollower and providing a simple arrangement for holding and positioning the same. Thequantity of fuel supplied by pumps of the this spill passage or by-pass opening is uncovered by the injection plunger as it approaches the end of this discharge stroke, the fuel thatv flows type to which the invention relates, iscommonly with particular with a plurality of cylinder bores ll, one for each of the required pump. The drawings disclose a pump which was designed with a large number of cylinders some of which have been omitted and the drawings contracted as indicated by the broken lines in Figures 2 and 3. Since the individual cylinders are identical a description of one of them will suflice to enable those skilledin the art to supply any desired number. This description will now be given cylinders of the multi-cylinder present inreference to Figure 1.. The'cylless diameter than the bore ll.

inder bore II is provided with anenlarged por-,

tion l2 at the upper end of the pump body ill to provide a shouldered portion 13, upon which rests a cylinder sleeve H; The cylinder sleeve I4 is formed of a heavy cylindrical block portion Hi from which a portion is of greatly reduced diameter projects downwardly into the bore II.

- The sleeve I4 is provided with a central bore "extending therethrough and of considerably The upper end of the bore i1 is closed by a disc l8 'havinga central orifice IS. A cylinder head 20, which is follower 31. The ball rides on the cam and thus reduces the friction between the cam and base portion 32 of the double plunger. The cam is thus effective to move the double plunger 33 upwardly, thereby effecting a pumping stroke for both the supply pump and the injection pump. The base portion 32 of the double plunger 30 is provided on its external surface with gear teeth 42 which mesh with coacting teeth 430i a rack detachably mounted-upon the pump housing It by nuts 2|, is provided with a cylindrical portion 22 adapted to enter the enlarged portion of the bore II and by bearing against a seal ring 23 hold the disc l8 securely against the upper surface of the cylindrical block l5 and thus maintain this member securely in position against the shouldered portion l3 of the bore 1 I.

Within the cylinder head is a cavity 24 adapted to accommodate a discharge valve 25 which is normally held in closing relation to the orifice l3 by a spring 26. The novel features of the discharge valve 25 are described and claimed in my co-pending application Serial No. 409,663

filed September 6, 1941.

' described. The double plunger comprises an outer cylindrical sleeve 3| of such external diameter as to make a fluid-tight sliding fit with the lower portion of the cylindrical bore I l. The

sleeve -3l projects from a base portion 32 of slightly less external. diameter than the internal '44 to the endthat longitudinal movements of the rack 44, which movements are imparted thereto in a manner hereinafter to be described, effect angular movements of the double plunger The pump housing III is provided with a side plate 45, detachably secured thereto by means of screwbolts 46, which side plate closes a cavity 41. The cavity 41 extends substantially the full length of the housing l0 and provides a fuel sump common to all of the cylinders. the sump from a suitable source by way of a nipple connection 48 formed on the side plate 45. A filter 49 is provided adjacent the fuel inlet and the bore II is provided with a passage 50 which passage provides communication between the fuel sump 41 and the interior of the pump chamber 34. As shown, the passage 53 opens into the pump chamber 34 at a point in the side wall thereof whic'h is immediately above the upper edge of the sleeve 3| when the latter is in its lowermost position as shown in Fig. 1.

' The upper, edge of the sleeve 3| which controls the passage 50 iscut on an angular bias with respect to the horizontal so that angular movement of the plunger will result in a variation in the extent of the upward stroke of the plunger before the passage 50 is closed, by the upper lip diameter of the bore II and a second sleeve 33 projects upwardly from the base portion 32 into the bore ll of the cylinder sleeve H with which it makes a fluid-tight sliding lit. The construction provides an annular space 34 in part between the cylinder bore l l and the external wall of the sleeve l6 and in part between the internal wall of the sleeve 3| and the external wall of the sleeve 33. The annular space 34 is utilized as t a supply pump chamber in a manner which will hereinafter be apparent.

space 34 is a compression spring 33 which bears at its upper end against the .block I! and at its lower end against the base portion 32 of the double'plunger 30 to bias the plunger in the direction of its lowermost; or outermost position.

' A plate 34' resting on ball bearings 33' is preferably interposed between the spring 33-and the base portion 32 to reduce the friction therebe tween and prevent twisting distortions of the of the sleeve 33. A check valve 3|, positioned in a cavity 52 of the cylindrical block portion I5, is normally held-by a spring 53 in closing position with respect to a passage 54, which passage forms the discharge or outlet from the pump chamber 34. As shown, the cavity 32 is formed as a countersunk bore extending downwardly from the upper'surface of the cylindrical blockl5 and accordingly is closed at its upperend by the disc it which forms the fixed bearing for the spring 33. A passage 53 connects the cavity" with the interior of the bore ll at'a point immediately above the upper edge of the sleeve 33 when the latter is in its lowermost position as shown .in

Fig. 1. A second passage I3 connects the cavity '-Within the annular i spring upon angular movements of the double,

plunger 30.

The base 33 on the lower side thereof and coaxial therewith which-cavity accommodates a ball cam'follower 31, preferably retained in the cavity by.

means of a spring 'ring 33. A cam shaft 33 is journalled in the lower portion of the pump housing ill by means of ball bearings 40 and carportion '32 is provided with a was I 32 with a channel-l1 formed in the interior of the housing I p, which channel forms a pressure supply reservoir common to all of the. pump cylinders. While onedischarge valve II, in a single cavity 32 together with the associated passages, is sumcient for one cylinder unit I pre-' fer to provide a plurality of these for each cylinder unit, as may be seen more clearly from Figure 2. which shows three such valves are provided'in the block I! on the side thereof adjacent channel 51. ,These are identical in form except that the passages 33 between the cavities 32 and the bore II are arranged toopen into the bore-ll at slightly different levels. Thus the central one of these cavities. has an openlnginto the bore H at the level of the section line 2-4. The-discharge .cavity to the left of this central one has a passage opening into, the bore 111 at a point ries a cam 4| positioned to contact the ball cam above the level of this section line, while that to the right has a e slightly below thesection line. The upper lip of the sleeve 33 is cut at a slight angle coinciding with the inclination Fuel is supplied to of a line defined by the openings of passages 58 1 into the bore.

The channel 61 is connected at one end of the housing I8 with a passage 68 which extends through the end'wall of the housing and provides communication with a passage 58 formed in a member 88 which as shown is rigidly attached to the end wall of the pump housing by means of screw bolts 8| but which if desired may be cast integrally with the housing. The passage 89 opens into a cylindrical chamber 82 formed in the member 88 which chamber contains a A passage 88 provided in the member 88 connects the discharge chamber 84 by way of pas- .sage 86- in the end wall of. the housing I8, with a channel 81 formed in the interior'wall of said piston 83. The piston 63 is rigidly connected to one. end of a rod 84, which end of said rod is provided with a cylindrical bore 68 extending lengthwise thereof and partially therethrough. A sleeve 66 extends into the bore 85, making a sliding fit therewith. The outer end of the sleeve 68 extends into a bore 81 in the outer.

end of the member 68 and is adjustably positioned by means of a block 68, which block is 4 provided with a central annular boss 68 prowith corresponding threads of an adjusting screw 13 which extends through the side wall of the member 88.

The block 68 is provided with a central longitudinal bore 14 which is internally threaded to coact with external threads, ona' rod 15. The rod 15 extends through and slightly beyond the ends of the adjusting block 68 and carries, upon a reduced portion 16, a cross bar'11, which cross bar extends through longitudinal slots 18 in the sleeve 66. The opposite end of the rod 15 projects slightly beyond the-outer'end of block 68, and is provided with a lock nut 19 which secures the rod 15 in any position relativeto the block 88 to which the rod may be adjusted.

Thus by turning the rod 15, while the block 68 is held stationary the cross bar 11. which does not rotate; with the rod, is moved toward or W away from the piston 68. and thereby determines the outermost limit of movement of the piston. The slots 18 are not sufliciently large to permit free flow of fuel between the pressure chamber 88 and the interior of the sleeve 88, and for this reason an additional opening 18 is provided in the sleeve 86 adjacent the pressure side of the piston 68. An end plug 88'closesthe outer end of the bore 14 and aids in retaining the parts in their adjusted position.

. A triangular slot 8| in the rod 64 provides an opening between the cylinder chamber 62 and the bore -65. A corresponding slot 82 in the varied by angular movements of 'the sleeve 86 imparted thereto through'block so, to which the sleeve is rigidly attached to the end that the communication between the two sides of the pishousing in the same manner as the channel 81 is formed on the opposite interior wall. One or more passages 88-c'onnect channel 81 with the fuel sump 41.

' 'At the end of the housing I8 remote from the hydraulic fuel control device, passages 88 and 98 connect the channels 51 and 81 with a chamber! provided in the end wall of the housing.'

A-valve 92 in the chamber 8| normally closes both of the passages 88 and 98, being biased in the closing direction bya spring. 83. A screw plug 84 closes the outer end of the chamber 8|, and provides a means for adjusting the tension of the spring 93.

The rod 84 of the hydraulic control device extends into the housing -I8 and has a'cutout portion 95 to accommodate an actuating pin 88 which-protrudes from. one end of a lever 81. The lever 81 is fulcrumed at a point intermediate its ends on a pivot pin 88,-which protrudes. from the outer face of an interior wall of the pump housing, and terminates in a forked end 89. A pin I88 which protrudes from the rack 44 is. embraced "by the forked end of the lever to impart movements of the lever to the rack. Accordingly reciprocative movements of the piston 63 and the attached rod 64 are transmitted by the lever -81 'to the rack 44, which rack imparts angular movements to the double plungers of each cylinder unit' and thereby alters the -ef-- fective capacity of the injection; plunger 88 of all units since each of these plunger-s is provided with an inclined slot |8I forming a spill passage through the wall of the cylinder sleeve I6, and an oppositely inclined slot I82 through the .wall

of the hollow plunger is. adapted to come into partial registration with the slot |8| toward the end of the discharge stroke of the plunger for a short distance therefrom for attachment to any suitable manual control means. A spring I84 is positioned between the enclosed ends of the rods 84 and I83,.,being seated in sockets pro vided in these ends, wherebymanual adjustments of the rod I88 varies the required force I required upon the face of the piston 88 to efiect.

a-given movement. of the rod 84 against the tension of the spring I84.

Where it is desired to control the timing of the pumpin accordance with the-engine speed and load as well as to controlthe quantity of fuel supplied, the additional elements requiredcan readily, be applied to, the mechanisms so the pump remote from the hydraulic control mechanism previously described}.. This housing ton 88 may be restricted toany'desired degree. 1

Longitudinal movement of the rod 84 also alters the eflectiv'e area of the opening.

I88 is providedwith a cylinder bore I88 having a piston I81 which divides the cylinder bore I88 into a pressure chamber I88 and a discharge chamber I89. An inlet passage II. is provided in the .end wall of the housing III-between the channel 81, which is the high pressure supply channel, and the pressure chamber I88. A piston rod III 'isrigidly connected with the piston I81 and is provided with a bore! extending partially therethrough from the piston end thereof.

A slot. H8 is provided in the sidewallof the bore H2 in a position to beadjustably covered by a control sleeve II4 which control sleeve is provided with a similar slot adapted to register with the slot H3 in the same manner as has previously been disclosed inconnection with the slots BI and 82 of the timing control mechanisms. The control sleeve H4 is angular-1y adjustable by means of an adjusting screw Hi to the end that communication between the pressure chamber I08 and the discharge chamber I may be relatively free or relatively obstructed by angular adjustment of the control sleeve H4. Movement of .the piston I01 to the right from the position shown in Figure 6 also tends to restrict communication between the pressure and discharge sides of the piston, the slots being triangular in shape as is disclosed in connection with the analogous slots of the timing device,. and shown in Figures 4 and 5. A discharge passage ll6 in the housing I connects the discharge chamber I09 with a passage II1 formed in the end wall of the pump'housing and this passage II1 opens into the channel 81 which channel as previously described permits the return flow of the fuel to the supply sump 41 by way of passage 88. The piston I01 is biased in the direction of the pressure chamber I08 by means of a spring H8. The piston rod II I projects outwardly of the housing I05 through a packing gland I I9 and is connected at its outer end with a lever I20. Th opposite end ofthis leve extends through an opening I2I in a housing I22 which housing is mounted upon the end wall of the pump surrounding the projecting end of the cam-shaft 39. The lever I is pivoted intermediate its end upon a pivot pin I23 positioned in the opening I2I. The free end of v lever I20 actuates a collar I24 which collar is provided with internal splines that coact with splines I25 formed on the end of the cam shaft. Similar internal splines at the'opposite end of the collar coact with splines I26 formed on the surface of a driving or stub shaft I21. The splines I26 and. I21 areso inclined relative to each other that longitudinal movement of the collar I24 shifts slightly the angular position of the cam 39 relative to the driving shaft I21.

Lubricant may be supplied to the pump by way of an oil spout I30 formed on a face plate I3I, which face plate closes an oil cavity .I32 formed in the housing I0 on the opposite side plunger has been so rotated that the lowermost portion of the lip of the sleeve 3I is adjacent the passage 50 then the plunger must move upward for a short distance before the passage 50 is obstructed and the effective capacity of the supply pump, that is the quantity of fuel that is forced into the cavity 52, is at a minimum. From the cavity 52, of which as previously mentioned there are'preferably a plurality, the fuel passes into the channel 51 which forms a pressure supply reservoir common to all of the cylinder units from which it may flow into the chamber of the high pressure pump after the tion of the double plunger also'rotates the inclined upper lip of the hollow injection plunger to .the end that the passages 55 are slightly more obstructed when the engine is rotating at high speed so that slightly less fuel will be admitted to the high pressure pump chamber under these conditions than would be admitted-at low speed. Upon th upward movement of the plunger fuel is forced past the discharge valve 25 and into the discharge conduit 29 whence it passes to the usual injection" nozzles (not shown). The uppermost portion of the inclined slot of the sleeve 33 passes the lowermost portion of the upwardly inclined slot ml in the wall of the sleeve I6 and, thus the remainder of the fuel is forced out through these slots back into the chamber 34 of the supply pump. It will be seen that upon rotation of the sleev 33 the uppermost portion of the slot in the wall of the high pressure plunger may be rotated to a point where it i not in alignment with the lowermost point of the oppositely-inclined slot'in the sleeve I6 thereof from the cavity 41. A filter I33 is posltioned between the face plate I 31 and the cavity I33 to the end that all of the lubricant passing through the oil spout to the cavity must pass through the filter. Since the cavity I33 contains the major parts of the fuel control mechanism these parts will be at least partially immersedin lubricant. Passages I34 connect the lower portion of the cavity I32 with the cam chamber .or later in the course of its upward movement.

When the plunger is so adjusted that the upper inclined lip of the sleeve 3| immediately obstructs this passage then the maximum fuel quantity of which the supply pump is capable is forced upon the upward movement of the plunger past the discharge valve 5|. When the;

thus under these conditions the plunger 33 must move farther in its upward stroke before the registration of any part of the two inclined slots is effected and thus the quantity of fuel that -is forced past the discharge valve 25 will be in-- creased before the passages which constitute the spill passage or by-passage is opened.

The capacity of the supply pump even when adjusted to its minimum capacity position is far greater than the capacity of the high pressure or injection pump so that from the plurality of plungers constituting a multi-cylinder pump a considerableexcess quantity of fuel is forced into the channel 51, which constitutes the supply reservoir, over and above that required for the injection pumps. This excess fuel flows by way of passages 58 and 50 into the chamber 62 where acting upon the outer face of the piston '63 it tends to force the rod 64 to the right against the action of spring I04. Movements of the rod 64 are transmitted by the lever 91 to the rack bar 44 which acts to rotate all of the double plungers to vary both the quantity of fuel available in the pressure reservoir 51 and the quantity of fuel supplied per pumping stroke-by each of the injection plungers. The fuel from the pressure chamber 63 passes to the discharge chamber 84 through the throttle opening formed by the two triangular slots 8| and 82, flowing either freely or with more or less restriction according may be closely approximate to the pressure on the intake side thereof or there may be a con- I siderable difference between these pressures depending upon whether the two slots are in complete or only partial registration. From the discharge chamber 84 the fuel passes by way of the return passage 85 and 86 to the channel 81 from which itflows' back to the fuel sump 41 by way of passages 80.

In the event of too great an obstruction to the passage of fuel being interposed between the high pressure reservoir 51 and the low pressure or discharge reservoir-81, the pressurein the chamber 51 acting upon the disc valve 92 will open the valve to permit the flow of fuel from the pressure reservoir 51 to the discharge reservoir 81 by way of passages 89 and 90.

The effective pressure required on the face of the piston 63 to effect a given movement of the rack 44 and accordingly a given adjustment of the capacity of the pumps may .be altered by any manual means such as an accelerator pedal or throttle lever connected with the rod I03.

Where it is desired to alter the timing of the pump that is to say the time of the injection strokes of the plungers relative to the stroke of the engine pistons the disc valve 92 may be omitted and the pressure chamber 51 and thedischarge chamber 81 are then in communication through the hydraulic timing control mechanism shown in Figures 6 and 7. In this case the fuel passes from the pressure channel 51 to the pressure chamber lll8- by way of the inlet passage H0 where it acts upon the face of piston ill! to move the same against the action of spring I08 until the forces are balanced.

The piston rod III is thereby moved to the right shifting the timing collar I24 to the left of the position shown in Fig. 7 and accordingly advancing the angular position of the cam shaft 39 relative to the driving or stub shaft I21. Thus the timing is dependent upon the pressure of the fuel in the channel 51. The pressure of the fuel in the pressure reservoir 51 is dependent in general, upon the speed of the engine by which the pump is driven, but is modified by the manual adjustment of the throttling orifice between the pressure and discharge sides of piston I01. a

From the above description it will be apparent that this invention provides a devicein which the various elements such as the supply pump for placing the fuel under an initial pressure, the injection pump for raising accurately measured quantities of the supplied fuel to the required injection pressure, together with the means for controlling the quantity of fuel supplied in accordance with the demand on the engine, and also where desired, the means for varying the timing of the pump in accordance with the speed of the engine, are all incorporated in a unitary structure. Furthermore by providing that each cylinder unit of a multi-cylinder pump shall include both .a supply plunger and an injection plunger I have combined both functions in a single cylinder unit. without increasing the number of parts since the sleeve which constitutes the plunger of the supply pump also acts .as the usual guide member for the injection plunger. It will also be noted that by the provision of the chamber of the supply pump enclosing the end of the sleeve forming the cylinder of the injection pump leakage around the injection plunger is by the increase in pressure in the supply pump chamber simullubricating oil around the actuating and control mechanism.

"It will likewise be apparent that the present invention avoids many other difliculties inherent in fuel injection pumps as at present constructed. It is current practise to use a supply pump having but one or two pump cylinders of relatively large capacity to supply an injection pump having six or more cylinders. This necessarily results in a material difference in the pressure of the fuel in the "pressure supply reservoir as between the pressure stroke of the supplyplunger and the suction stroke thereof. 'By providing a structure in which there are as many supply plungers as injection plungers such variations in pressure in the supply reservoir are avoided the quantity of fuel supplied to one .of engine cylinders and that to another on this account,

' and the smoothness of engine operation is accordingly improved. The, absence of pressure pulsations in the fuel supply reservoir is of course all the more desirable where the fuel supply pressure is utilized to control the quantity of fuel supplied to the engine or the timing thereof.

While there has been herein described but a single embodiment of the invention other embodiments and modifications incorporating the advantageous features and novel functions of the form herein disclosed, and lowing claims will be apparent to those skilled in the art.

Having thus described the invention, I claim:

1. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of said housing, each unit constituting a supply pump plunger, said double plunger smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, 9. cylinder sleeve having a boreformlng a pump chamber for said injection plunger, said sleevehaving one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chambers.

2. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a double plunger, said double plunger comprising, a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, a cylinder embraced by the fol-' cylinder units mounted in sleeve having a bore forming a pump chamber for said injection plunger,.said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receivin fuel discharged from said supply pump chambers, and conveying the same to said injection pump chambers, and a single means for simultaneously altering the effective capacity of both said supply pump and said injection pump.

3. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder unit mounted in said housing, each unit constituting a supply pump and an injection pumpand including a double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed -in said pump housing and common to all .of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chamber, and means actuated by the pressure in said pressure chamber for controlling the quantity of fuel delivered by said injection plunger,

4. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a double plunger, said double plunger comprising a pair of concentric plungers of different diameter, th smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel'discharged from said supply pump chambers, and conveyingthe same to said injectionpump chambers, and means ac.- tuated by the pressure in said pressure chamber forcontrolling the quantity of fuel supplied by said supply pump to said pressure chamber.

5. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger 2. supply plunger, a cylinder formin a pump chamber for said supply plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in saidsupply pump chamber, a pressure supply chamber'formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chambers, and means actuated by the pressure in said pressure chamber for controlling the quantity of fuel supplied by said supply pump to said pressure chamber and the quantity of fuel supplied by said injection pump to the engine;

6. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a, double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump'chamber for said supply plunger, 9. cylinder sleeve having a bore forming a, pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receivin fuel discharged from said supply pump chambers,

and conveying'the same to said injection pump chambers, a hydraulic control device rigidly connected with said housing. and actuated by the pressure in said pressure supply chamber.

7. A combined supply and injection pumpfor internal combustion engines comprising a pump housing, a plurality of cylinder units mountedin said housing, each unit constituting a supply pump and an injection pump and including a double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injectiom plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chambers, a hydraulic timing control device and a hydraulic fuel supply control device both rigidly connected with said housing on opposite ends thereof and actuated by the pressure in said pressure supply chamber.

8.'A pump including a cylinder, a plunger reciprocative therein, means to supply fuel to the interior of said cylinder, connecting means whereby a portion of the fuel supplied to said chamber is forced by said plunger to the point of use, and means to return a controlled portion of the fuel in said cylinder to the intake side of the pump said means including a slot in the side wall of the cylinder forming an elongated opening therethrough, and a corresponding slot in said plunger said slots being inclined relative to each other whereby the portion of the two slots in registry continuously changes during the discharge stroke of the plunger. 7

9. A pump including a cylinder, a plunger reciprooative therein, means to supply fuel to the interior of said cylinder, connecting means whereby a portion of the fuel supplied to said chamber is forced by said plunger to the point of use, and means to return a controlled portion of the fuel in said cylinder .to the intake side of the pump said means including a slot in the side wall of the cylinder forming an elongated opening there through, and a corresponding slot in said plunger said slots being inclined relative to each other whereby the portion of the two slots in registry continuously changes during the discharge stroke of the plunger and means for rotating said plunger to vary the point in said discharge stroke internal combustion engines comprising a pumphousing, a plurality of cylinder mountedin .said housing, each unit constituting a supply pump and an injectionpump and including a double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting aninjection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply-plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chamber said sleeve having a spill passage extending therethrough and controlled by said injection plunger, whereby the excess fuel from the chamber of said injection pump is discharged directly into the chamber of said sup- P y P p; I

11. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a,

double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger a supply plunger, 8. cylinder forming a pump chamber for said supply plunger, 2. cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chambers said sleeve having a portion of larger diameter than said cylinder of said supply pump, a cylinder head having a portion bearing upon said enlarged portion of said sleeve whereby any cylinder unit of said pump may be removed as a whole upon removal of the corresponding cylinder head.

12. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply double plunger, said. double plunger comprising a. pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger a supply plunger, a cylinder forming a pump chamber for said supply plunger, a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for'receiving fuel discharged from said supply pump chambers, and conveying the same to said injection pump chamber a hydraulic control device rigidly connected with said housing and actuated by the pressure in said pressure supply chamber a discharge chamber within said housing in communication with the discharge side of said hydraulic control device and incommunication with the suction side of said supply pump internally of said housing, and means for discharging fuel from said pressure chamber to said discharge chamber upon excessive pressure in said pressure chamber. v

14. A fuel injection pump including a cylinder, a plunger reciprocative in said cylinder, said cylinder having a by-pass passage controlled by said plunger, means to rotate said plunger to vary the quantity of fuel supplied by said pump by altering the quantity-of fuel ejected through said .by-pass passage, said cylinder having inlet I passages also controlled by said plunger to adpump and an injection pump and including a I double plunger, said double plunger comprising a pair of concentric plungers of different diameter, the smaller constituting an injection plunger and the larger 2. supply plunger, a cylinder forming a pump chamber for said supply plunger,- a cylinder sleeve having a bore forming a pump chamber for said injection plunger, said sleeve having one end terminating in said supply pump chamber, a pressure supply chamber formed in said pump housing and common to all of said units for receiving fuel discharged from said supply pump chambers, and conveyingthe same to said injection pump chamber a hydraulic control device rigidly connected with said housing and actuated by the pressure in said pressure supply chamber a discharge chamber within said housing in communication with the discharge side of said hydraulic control device and in com munication with the suction side of said supplypump intemally of said housing.

13. A combined supply and injection pump for internal combustion engines comprising a pump housing, a plurality of cylinder units mounted in said housing, each unit constituting a supply pump and an injection pump and including a mit fuel into said cylinder when said plunger 'approaches the end of its suction stroke, said inlet passages being spaced circumferentially and longitudinally of said cylinder and said plunger having an inclined lip corresponding to the inclination defined by the spacing of said inlet passages, whereby rotation of said plunger to vary quantity of fuel ejected'through said bypass passage also slightly restricts theopenings of said inlet passages into said cylinder to reduce the quantity of fuel admitted to said cylinder through said inlet passage at high speeds of said pump. 1

15. A fuel injection pump including a housing, a plurality of pump cylinders disposed in'said housing, said housing having a cavity formed in one side thereof constituting a fuel supply sump common to all of said cylinders, a face plate detachably secured to said housing and forming a closure for said cavity, a second cavity formed in the opposite side of said housing from said first mentioned cavity and forming a reservoir for lubricant, and a second face plate detachably secured to said housing forming a closure for said second cavity.

16. A fuel injection pump including a housing, a plurality ofpump cylinders disposed in said housing, said housing having a cavity formed in one side. thereof constituting a fuel supply sump common to all of said cylinders, a face plate 'detachably secured to said housing and forming cavity formed in the opposite side of said housing from said first mentioned cavity and forming a reservoir for lubricant, a second face plate detachably secured to said housing forming a closure for said second cavity, and means to supply lubricant to said second cavity through said second face plate. 1 v

17. A fuel injection pump including a housing,

'- a plurality ofpump cylinders disposed in said housing, said housing having a cavity formed in" one side thereof constituting a fuel supply sump' tachably secured to said housing forming a closure for said second cavity, means to supply lubricant to said second cavity through said second face plate, and filters adjacent each of said face plates for filtering the fuel and lubricant passing to said cavities through said face plates. LOUIS BEEH. 

